What are the maximum drive level requirements for the crystal used for the FX2LP? The datasheet shows a 500uW minimum, while the CY4661-External USB hard disk drives and FX2LP DMB-T/H TV dongle reference designs use 100uW and 200uW max drive level crystals. Have there been any reported issues using 100uW or 200 uW max drive crystals. Due to space constraints, I am looking at using a 300uW max drive level crystal.
A 500 uW maximum drive level crystal is recommended since the power dissipation of the crystal can go upto 500uW with FX2LP and it will exceed the maximum drive level for a 300uW crystal which can cause ageing and reduction in accuracy. Kindly check the App Note for further crystal requirements.